A Seamless Web Integration of Adaptive HTTP Streaming

Nowadays video is an important part of the Web and Web sites like YouTube, Hulu, etc. count millions of users consuming their content every day. However, these Web sites mainly use media players
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Nowadays video is an important part of the Web and Web sites like YouTube, Hulu, etc. count millions of users consuming their content every day. However, these Web sites mainly use media players based on proprietary browser plug-ins (i.e., Adobe Flash) and do not leverage adaptive streaming systems. This paper presents a seamless integration of the recent MPEG standard on Dynamic Adaptive Streaming over HTTP (DASH) in the Web using the HTML5 video element. Therefore, we present DASH-JS, a JavaScript-based MPEG-DASH client which adopts the Media Source API of Google’s Chrome browser to present a flexible and potentially browser independent DASH client. Furthermore, we present the integration of WebM based media segments in DASH giving a detailed description of the used container format structure and a corresponding Media Presentation Description (MPD). Our preliminary evaluation demonstrates the bandwidth adaption capabilities to show the effectiveness of the system.

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DASH-JS (cont’d)• Bandwidth / throughput estimation – … is done each time a segment is retrieved – At the beginning the MPD is used to have an educated guess on the bandwidth – To bypass proxy caching “no-cache” is set in the HTTP Request Header (will influence the throughput estimation)• Representation selection is based on: w1bn-1 + w2 bm bn = w1 + w2 – bn-1 denotes the throughput calculated at the n-1th segment – bm depicts the throughput measured with the nth segment – bn is used to decide which representation should be selected – The weights (w1 and w2) are used to mimic optimistic or pessimistic behavior• Simple adaptation logic, easy to extend, modify…2012/08/30 http://dash.itec.aau.at 7